Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Colon cancer survival linked to number of lymph nodes examined

21.03.2007
An analysis of 17 studies from nine countries has found that the more lymph nodes that are removed and examined during surgical treatment of colon cancer, the better the outcome appears to be for patients.

The study suggests that removal of the nodes takes away a reservoir for potentially lethal cancer, and that knowing how far a cancer has spread leads to tailored and more beneficial treatment, according to researchers at The University of Texas M. D. Anderson Cancer Center.

Investigators say the findings, reported in the March 21 issue of the Journal of the National Cancer Institute, encourage a dialogue amongst physicians regarding the number of lymph nodes removed by surgeons and evaluated by pathologists as a measure of the quality of care that colon cancer patients receive.

"Currently just over one-third of colon cancer patients in the United States are getting an adequate lymph node evaluation," says the study's lead author, George Chang, M.D., assistant professor in the Department of Surgical Oncology at M. D. Anderson.

The results of this study were striking and should help support efforts now ongoing by some medical professional societies and expert panels to consider a minimum number of lymph nodes be extracted and examined during the surgery, continues Chang.

For example, the research team reports that one of the 17 studies examined, a national clinical trial enrolling more than 3,200 patients to look at the effects of chemotherapy on colon cancer recurrence after surgical resection, demonstrated a 14 percent increase in five-year survival if more than 20 lymph nodes were examined, compared to less than 11 nodes among patients who have Stage II cancers. The survival advantage was even greater - 23 percent - in patients with Stage IIIA and IIIB cancer if more than 40 nodes were evaluated, compared with less than 11 nodes.

All but one of 17 studies of Stage II cancer showed the same association between the number of nodes evaluated and improved outcome, as did four of six studies of more advanced cancer, Chang says.

"This tells us that surgeons and pathologists involved in the care of colon cancer patients should make every effort to improve their collection and evaluation of lymph nodes."

Removing colon tissue during surgery in a way that captures all of the tumor-associated lymph nodes requires attentiveness, Chang acknowledges. A surgeon needs to trace back the origins of blood vessels closest to the tumor because the lymphatic system, with its nodes, closely tracks with the blood system.

Sometimes the nodes, which filter cancer cells from the lymph, can be difficult for pathologists to find, especially when the lymph nodes are small or when the patient is obese. "Everyone is different," he says. "Some people have more nodes, some people have fewer; nodes can be large and easy to identify or small, and the number may differ depending on which part of the colon contains the tumor. The factors that determine the total number of lymph nodes are not all together known."

These findings also should serve as an empowerment tool for patients in need of colon cancer surgery.

"Health care consumers are told all the time to ask surgeons how many operations they have done, but I think in this case they should ask how often they do colon cancer surgery. Surgeons responsible for the majority of these procedures do them infrequently," says Chang.

Studies have found that 70 percent of colon cancer resections are performed by general surgeons who do less than 10 of these surgeries a year, and that colon cancers removed by surgeons who perform colon cancer surgery more frequently are more likely to have more lymph nodes examined.

"We are not suggesting surgeons cut out more colon than necessary, but that they abide to the principals for cancer surgery, and that pathologists follow up in kind," Chang says.

Because all of the studies examined were observational, the researchers stress that they cannot definitively say increasing the number of lymph nodes examined leads to improved survival. Such a statement could only be supported by a randomized, controlled clinical trial - which would not be ethically possible to do.

Laura Sussman | EurekAlert!
Further information:
http://www.mdanderson.org

More articles from Studies and Analyses:

nachricht Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung

nachricht Scientists reveal source of human heartbeat in 3-D
07.08.2017 | University of Manchester

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Nagoya physicists resolve long-standing mystery of structure-less transition

21.08.2017 | Materials Sciences

Chronic stress induces fatal organ dysfunctions via a new neural circuit

21.08.2017 | Health and Medicine

Scientists from the MSU studied new liquid-crystalline photochrom

21.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>